On-screen signal generating apparatus for a cable television

摘要

An on-screen signal generating apparatus for a cable television system is capable of displaying the control commands from a remote control while watching television. A memory circuit stores color information for each pixel needed for displaying the control commands on the screen. A main control circuit receives the color information stored in the memory circuit for output to RGB latches, and generates input/output port selection signals and writing signals for latches. The latches output the pixel data to D/A convertors for converting the display data to analog format. The analog signals are then combined with the original video signal.